YZ144 Power Valves

[gruberyz]

Does anyone know if the power valves from a 2006 Athena 144 kit will fit in the stock YZ125 cylinder? I'm not concerned with making max power as I'm detuning my daughters MX YZ144 to a woods racing heavy flywheel 125. I'm not having much luck keeping the 144 running more than about ten hours and that's ok doing five lap MX races but not going to work on two hour cross country events.

[BRM]

I don't think the athena power valves will fit the OEM cylinder. What seems to be wrong with the Athena kit? Is it blowing head gaskets? This has been an issue with the earier kits.

This is a fixable problem.

[gruberyz]

Yep it blows head gaskets. I've put three in in the last month. will run about an hour then start passing coolant into the motor. Also have to run race fuel or it detonates

Edited January 27, 2012 by gruberyz

[BRM]

Do a search on here regarding athena 144 and problems.

If I recall correctly there was specific setups that eliminated the seals blowing.

Later model athena 144s used a one piece head which I hear eliminates the issue.

This is fixable for minimal cost.

Then you keep the 144 and just add a Flywheel weight and gear it up a bit and the bike will be tamer for offroad but will have good topend speed.